Upon encystment, Azotobacter vinelandii synthesizes five n-alkyl resorcinols and two n-alkyl pyrones. There are two chain length homologs of each molecular species and they are found in cyst membranes. The "resorcinol synthetase" will be extracted from enzysting cells and purified. Its catalytic properties and molecular composition will be compared to that of the fatty acid synthetase (FAS) of vegetable cells in order to determine whether "resorchinol synthetase" is a unique enzyme complex or a modification of FAS. Model membranes (lipid bilayers) will be prepared from vegetative cell A vinelandii phospholipids and various levels of resorcinols and pyrones from cysts. Physicochemical properties of these systems will be studied in an effort to understand the effect that the unique cyst lipids exert on the membrane properties. In parallel studies, membranes from cells at various states of encystment and germination will be isolated and assayed for cytochrome levels, electron transport, and bound enzyme activities as a function of their lipid composition. Similar measurements will be made on intact cells to determine which cellular elements change their association with membrane as lipid composition changes.